High-risk meningiomas always require postsurgical radiation treatment. Recent evidence has shown that increased radiation therapy dose may be associated with increased intracranial control of disease. In order to better define the volume of radiation treatment, the addition of PET imaging with somatostatin receptor tracers adds additional information compared to encephalon MRI with MoC alone.The present study aims to investigate whether radiation treatment with higher doses than the standard and defined using PET imaging can be safe and at the same time effective in order to increase progression-free survival in high-risk meningiomas.